(3) Normal ECG (Johnston) Flashcards
Draw out a normal EKG with:
P wave
QRS complex
T wave
U wave
Draw out a normal EKG with:
PR interval
PR segment
QRS interval
ST segment
QT interval
What does each SMALL SQUARE represent in time?
0.04 seconds
What does each LARGE square represent in time?
0.2 seconds
PR interval should not exceed ____ seconds
0.2
If the PR interval is longer than 0.2 seconds, that indicates…
1st degree AV BLOCK
What is the PRIMARY pacemaker of the heart?
SA node
If the SA node fails, what takes over as the pacemaker of the heart?
AV node
What event is occuring during the p wave?
Atrial Depolarization
P Wave
Should be upright in:
Leads I and II
V4, V5 and V6
AVF
P wave should be inverted in:
AVR
Describe what the P-R interval is:
Beginning of P wave to beginning of QRS complex
*Time from SA Node to ventricular muscle fiber
What is the normal range for the P-R interval?
0.12- 0.20 seconds
(3 small squares to 5 small squares)
What event occurs during the QRS complex?
Ventricular Depolarization
What is the normal time frame for the QRS complex?
0.05-0.10 seconds
Q waves shouldn’t be more than ___ seconds in width
0.03 seconds
What are you looking for with the ST segment?
Observing the level relative to baseline and shape
Normally is isoelectric
What is occuring during the T Wave?
Ventricular repolarization
QT duration can give us insight into the following pathologies:
Myocardial Ischemia
Myocardial Injury
Myocardial Infarction
Pathologies:
What would indicate a pathology with a T wave?
INVERTED T WAVE = indicates an ischemic pattern
TALL UPRIGHT T WAVES = Hyperkalemia
P-R should be less than…
0.2 seconds
QRS should be less than…
0.12 seconds
What heart rate is considered tachycardia?
HR > 100
What heart rate is considered bradycardia?
HR < 60
